Conduit fastener



Dec'. 28, 1943. l H. R. ELLlNwooD- 2,338,031

CONDUIT FASTENER Filed Sp'b.' 25, 1940 Patented Dec. 28, 1943 CONDUITFASTENER Herman Ray Ellinwood, Burbank, Calif., assignor to AdelPrecision Products Corp., Burbank, Calif., a corporation of CaliforniaApplication September 25, 1940, Serial No. 358,366 Claims. (Cl. 174-40)The present invention relates to an improved conduit fastener or clip ofthe type shown in the patent of Paul W. Adler, No. 2,215,283, issuedSeptember 1'1, 1940, and also disclosed in my Patent Nos. 2.291,88? and2,279,866 issued on August 4, 1942 and April 14, 1942, respectively.

The primary purpose of the present invention is to provide a clip orfastener of the character described in which a metallic conduitembracing strap, a rubber or similar cushion, and a metallic groundingstrip are so constructed and relatively arranged that the cushion andgrounding strip will be securely held at all times in position tomaintain an effective cushioning action and insure a positive electricalgrounding of the conduit to the metallic structure to which the strap isattached, regardless of the imposition of vibratory and other stresseson the conduit, strap, cushion and strip and the resultant tendency ofthe conduit to move relative to the strap and thereby dislodge thecushion and strip from proper position.

A further and more specific purpose hereof is to provide a clip of thecharacter described in which the conduit embracing portion or themetallic strap is of channelled cross section and the cushion is-eithermade to lie and be held in the channel of such portion or itselt` formedwith a channel for receiving the conduit embracing portion of the strapwhereby in either case the flanges or sides of the channelled portionwill retain the cushion strap and grounding strip in a predeterminedoverlapping relation regardless of the aforesaid. relative movement anddislodgement tendency resulting from vibratory and other stresses.

Another purpose of this invention is to provide a conduit anchoragedevice of the character described in which the full cushioning action ofa cushioning member arranged between the strap and the conduit isafforded While said member is compressed between the strap and conduitand without causing the dislodgment of the cushion from predeterminedposition relative to the strap and conduit or interfering with an effective electrical contact of the grounding strip with the conduit andstrap.

A further purpose of this invention is to pro# vide a conduit clip ofthe character` described wherein the metallic grounding strip isassociated with the cushion as by being carried in non-tensionedcondition thereon and is presented thereby so as to maintain electricalcontact of the maximum portion thereof with the strap and conduit, andthereby insure a reliable grounding of the conduit and at the same timeprovide adequate cushioning of the latter, said strip and cushion beingcapable of relative movement without impairment of their respectivefunctions, due to manner of constructing the strip andl cushion and therelative arrangement thereof.

' Another purpose of this invention is the provision of a clip such asdescribed in which the 'metallic grounding strip is mounted on therubber or like cushion member in such manner that considerable saving intime and labor is effected in assembling the cushion strip unit.

With the foregoing objects in view, together with such other objects andadvantages as may subsequently appear, the invention is carried intoeffect as illustrated by way of example in the accompanying drawing, inwhich: l

Fig. 1 is a fragmentary perspective view of a clip embodying myinvention, as when in use;

Fig. 2 is a vertical section of the clip as when not in use;

Fig. 3 is a sectional view on the line 3-3 o Fig. 1;

Fig. 4 is an enlarged fragmentary vertica1 section of the clip, as whenin use, showing also a part of the conduit;

Fig. 5 is a 4fragmentary perspective view of a modied form of clip aswhen in use;

Fig. 6 is a'vertical section of the clip of Fig. 5 as when not in use;

Fig. 7 is a sectional view on the line l-l ol' Fig. 5;

Fig. 8 is an enlarged fragmentary section of the :lip of Fig. 5 as whenin use;

Fig. 9 is a fragmentary perspective view of another modified form of theinvention as when 1n use; I

Fig. 10 is a vertical section of the clip of Fig. 9

as when not in use;

Fig. 11 is a cross section on the line lI l-ll of Fig. 9;

Fig. 12 is a cross section on the line l2-l2 of Fig. 10.

to be secured by means ofa screw 3 or other fastening to andelectrically contacted with a metallic structure (Fig. 1) which forexample is a structural part C of an airplane or the like.

On the inner periphery of the loop portion l is anelongated soft rubber0r similar resilient cushion member 4 which substantially surrounds andaffords a cushioned support for the conduit, and has associatedtherewith in the particular manner of this invention a metallicgrounding strip 5 arranged to contact the conduit and the straprespectively whereby the conduit will be grounded to the structure Cthrough the strap to prevent dangerous static discharges.

In accordance with the present invention, the loop or line embracingportion I is of channel cross section with its concave side and flanges6 outermost and the flat or inner side thereof supporting the cushion 4.This cushion is considerably wider than the portion I of the strap andis formed of channelled cross section so that the portion I may befitted in the channel thereof with its sides or flanges 6 abutting theinner faces of the flanges 1 on the cushion as shown in Fig. 3. In thismanner the loop portion I is effectively encompassed by andsubstantially embedded in the cushion and the interlock of these partsprovided by seating the portion I in a channel in the cushion asaforesaid prevents relative movement thereof and insures that thecushion Will not be dislodged or displaced from the strap incident tovibratory and other stresses which tend to effect a relative movement ofthe clip and conduit line. Moreover the relatively Wide cushion insuresa better cushioning support for the line in that it absorbs allvibratory and other stresses in such manner as to provide a permanentlysecure and reliable vibrationproof and static proof anchorage of theline.

In order to present large areas of the metallic grounding strip forelectrical contact with the line embracing portion I of the strap andthe conduit line B respectively, the cushion 4 may be i formed with alongitudinal series of spaced openings or slots 8 therein. Through theseopenings a plurality of folded, looped or doubled back portions 9 of thestrip 5 are extended so as to lie folded back on the outer surface ofthe cushion for contact with the loop portion I of the strap,

while the remainder ofthe strip in form of a longitudinal series ofsegments l0 provides a nearly continuous portion (see Figs. 1, 2 and 4)Vlying upon the inner surface of the cushion for contact with theconduit. Thus it is seen that a plurality of slightly spaced portions orsegments of the strip are disposed on the inner and outer faces of thecushion substantially throughout the length thereof, for contact withthe conduit B and loop portion I respectively, whereby to insure a goodelectrical contact with such parts and an effective grounding of theconduit to the structure C'. The ends I I of the grounding strip 5 arebent around the ends of the cushion 4 and lie between the cushion andthe strap in contact with the latter as shown in- Figs. 2 and 4.

It should be noted that lthe strip 5 is non-tensioned and is supportedby the cushion in such manner that the resilience and cushioning actionof the cushion are not impaired. Moreover, the strip 5 may be movedrelative to the cushion and yet afford an effective ground connectionbetween the line and thestrap regardless of distortion thereof andstresses placed on the strip as when and also due to vibration and otherstresses irnparted to the line.

It should-also be noted that if desired the cushion 4 `may be cemented,glued or similarly securedto the loop I.

Inadditionto providing for an intertting and interlocking of the strapand cushion to prevent tightly clampingv the" clip on the-conduit line,v

dislodgment thereof, the channelled formation of these parts materiallyreinforces and strengthens them. l

A modified form of clip embodying the present invention, as shown inFigs, 5 to 8, inclusive, follows the same Ageneral construction as theform shown in Figs., 1 to 4, inclusive, as to the bendable and resilientmetal strap I2 apertured ends I3, fastening I4, rubber or similarcushion I5 and metallic grounding strip I6, except that the strap ischannelled so that the concave side and flanges I1 thereof are innermostand encompass the cushion. This cushion is rectangular in cross sectionand fits in the channel of the strap between the flanges I1 for contactwith the conduit line I8. The strip I6 is wound helically around thecushion and therefore presents a plurality of portions on opposite sidesof the cushion for contact with the conduit and strap to ground thelatter to the metallic structure I9 as shown in Fig. 5.

In this form as in the one first described, the strip is non-tensionedand supported on and by the cushion so as to be movable relative theretoand compressed thereon without interfering with a reliableelectricalconnection thereof between the strap and conduit line.

It should be noted that in this form the portions of the strip I6crossing the longitudinal edges of the cushion will contact the flangesI'I of the strap as an added electrical connection between the strip andthe strap. In this connection it should also be noted that the rubbercushion is compressed when fitted between the flanges I1 whereby itistensioned and thereby frictionally heldin the channel of the strap. Thiscondition also obtains Iin the form of clip shown in Figs. 1 to 5,inclusive, since the cushion 4 is stretched and thereby tensioned whenthe loop portion I is fitted between the flanges 1.

Thel helical winding of the metallic strip I6 around the cushion fromend to end of the latter makes for a quick and easy 'assembly of thecushion strip unit and affords a maximum of contacting surfaces betweenthe strip and the conduit line and strap. In this form of clip thecushion may be cemented or otherwise secured on the strap if desired.v

Another modified form of clip embodying the invention hereof is shown inFigs; 9 to 12, inclusive, and includes a bendable, resilient metal strap20 for embracing a. conduit line 2 I, a resilient cushion member 22 ofsoft rubber or the like supported on the strap, a metallicgroundingstrip 23 carried by the cushion, aperture ears or terminals24on the strap and a fastening 25 forsecuring the strap to and inelectrical contact with a metallic structure 26. In this form of clipthe line embracing portion 21 of the strap is of channeled form but isarcuate or semicircular'in cross section with its concave sideinnermost. |The cushion member 22 is of circular cross sectionand fitsin and conforms to the channel formed by the concave side of the lineembracing portion 21 of the strap. 'I'he metallic strip 23 is woundhelically around the cushion from end to end thereof, is non-tensionedand-'free to' move relative. thereto, and like the other forms of theinvention affords a plurality of segments orv portions which contactthestrap and conduit line to insure a reliable grounding I of the linethrough the strap'to the structure 26.

compressible resilient in -place against dislodgment tendencies causedby vibratory and other stresses on the conduit line. However, as in theother forms of clips hereinbefore described the cushion 2,2v hereof maybe cemented or otherwise secured in the concave side or channel of thestrap, if desired.

As shown in Fig. 11, the cushion 22 may be compressed so that theconduit engaging portion is flattened when the strap is tightly securedaround the line and to the supporting structure 26. This cushion inbeing of circular cross section affords a full and effective cushioningaction and facilitates vthe incorporation of the grounding striptherewith.

1. In a clip for supporting a metallic conduit line on and electricallygrounding it to a metallic support, a metallic line embracing strapmember having terminals adapted to be secured to the metallic support, acompressible resilient line embracing and cushioning member ofinsulation vmaterial carried on the strap member, and a metallicflexible grounding strip lying upon one' face of the cushioning memberand having doubled portions which extend through the cushioning memberand lie upon the other face thereof whereby the portions of said stripon said faces will contact the strap member and the line respectively.

2. In a clip for supporting a metallic conduit line, a bendableresilient metallic strap member for embracing a metallic conduit lineand having terminals for attachment to a support, and a line embracingand cushioning member of insulation material carried by saidy strapmember, opposed and contacting flanges on the margins of said membersfor holding said members assembled, and means on the cushioning memberfor electrically connecting the line with the strap member.

3. In a' clip for supporting a metallic conduit line, a bendable.resilient metallic strap member for embracing a metallic conduit lineand Vhaving terminals for attachment to a support, and a compressibleresilient line embracing and cushioning member of insulation materialcarried by said support, and marginal anges on both of` said memberscontacting to hold said members against relative movement axially of theclip.

4. In a clip for supporting a metallic'conduit line, a bendableresilient metallic strap member for embracing a metallic conduit lineand having terminals for attachment to a support, a compressibleresilient lline embracing and cushioning member of insulation materialhaving opposed marginal anges defining a channel'vin which said strapmember is mounted, opposed marginal flanges on said strap memberabutting inner faces of the flanges on the cushioning member, and meansassociated with said members for establishing an electrical groundconnection between the strap member and said line.

5. In a clip for supporting a metallic conduit line on and electricallygrounding it to a metallic support, a metallic line embracing strapmember having terminals for attachment to the support, marginal flangeson said strap member, a resilient line embracing cushioning member ofinsulation material mounted on said strap member so that margins thereof-will engage the anges and are retained thereby, said cushioning memberhaving openings therein, and a metallic grounding strip associated withthe said members and carried by one thereof for effecting andmaintaining an electrical ground connection between the line and saidstrap member, said grounding strip having double portions extendedthrough said openings and vbent back to lie on one side of the cushionmember for contact with the strap member while other portions of thestrip lie on the other side of said cushioning member for contact with aconduit line.

HERMAN RAY ELLINWOOD.

